New research confirms what pessimists have always suspected: people are selfish, and if you're not, everyone will hate you.

According to ScienceDaily, psychologists at Washington State University had subjects played a game in which they could exchange points for meal vouchers. Participants disliked greedy players — those who tried to hoard all the points and vouchers for themselves. But they also didn't like extremely un-greedy players — people who willingly gave up points without taking vouchers in return. Other players were likely to say they didn't want to team up with these unselfish folks again, explaining that "the person is making me look bad" or could have an ulterior motive. Although unselfish behavior was actually good for the team as a whole in the game, participants still saw it as bad for them — says lead study author Craig Parks, "What is objectively good, you see as subjectively bad."

On the one hand, this is pretty depressing — people apparently hate and even fear altruism. But from a social point of view, it's not all that surprising. If you've ever seen a kid try to win friends with excessive gifts and self-sacrifice (say, giving up her fruit snacks without getting anything in return), you'll know it doesn't usually work. People expect a certain degree of self-interest, and they get upset if they don't see it — and in a way, this frees up other people to be self-interested. One take-home message of the study could be that it's okay, and even socially beneficial, to look out for yourself and take care of your own needs. You don't have to give up everything for other people — and in fact, they'll probably be suspicious if you do.